Ingredient costs are typically one of the highest economical components encountered when producing products intended for human or animal consumption. Processes such as aging, drying, curing, etc. slow the availability of such ingredients to the manufacturer as well as increase the overall costs due to the added inventory carrying time and treatment steps that are necessary to produce such a product.
A typical dry or semi-dry sausage fermentation process generally requires a long period of time, typically on the order of at least about 10 to 24 hours. This duration of time is necessary, in that by holding the sausage product for a sufficient amount of tmie allows the bacterial culture to metabolize the sugars that are present in the sausage meat admixture. This slow fermentation process has been used because the process preserves the textural properties of the meat product and limits the amount of protein denaturation that occurs, while providing a fermented product flavor to the dry and semi-dry sausages such as pepperoni and the like.
The acidulation of meat products, particularly meat emulsions, is well known. Meat emulsions, such as sausage emulsions, are mixtures of lean meat or meat protein and water that form a matrix in which fat particles, salt, sugar and curing agents are dispersed.
Acidulation of meat products in the past has been accomplished by various means. One such method comprises inoculating the meat mass with a small amount of previously fermented food. The resulting inoculated food mass is then allowed to ferment for an extended period of time. However, fermentation using this method is very slow because of the time required for bacteria to grow and produce acids (usually lactic acid) which eventually lower the food pH to the desired level required for dry and semi-dry sausage products.
Another method of acidulating food includes the addition of acid directly to the food product that is being prepared. This process, which quickly facilitates the reduction of the pH of the meat mixture has negative implications on the resulting flavor and texture of the resulting meat product and may destroy valuable textural properties if the process is not constantly monitored.
Dry and semi-dry sausage products are classified by the United States Department of Agriculture (“USDA”) according to process conditions, finished product pH, finished product moisture to protein ratio and other factors. For example, in order to meet the criteria for pepperoni, the product must have a finished product moisture to protein ratio of 1.6 to 1 and be processed under conditions specified by the USDA sufficient to kill trichinae. In order to meet the criteria for beef summer sausage, the product must have a finished product moisture to protein ratio of 3.1 to 1 and a finished product pH of no greater than 5.0.
A conventional process for making dry and semi-dry sausage products typically includes the following steps: Initially, adding and mixing (admixing) ground meat (pork, beef and/or poultry) with spices, curing agents and either an acid-producing bacteria, e.g., lactic acid-producing bacteria or an acidulant. The types of meat, spices and curing agents employed depend upon the type of sausage product desired.
Next, the meat mixture is formed into the desired shape by stuffing the mixture into casings of prepared animal intestine or synthetic material which are tied shut at both ends to form a single cylindrical unit or at intervals to form lengths. The mixture must be pre-formed into the tubular shape before the bacteria produces a significant amount of acid, or as is otherwise imparted to the admixture. The bacterial culture or acidulant quickly lowers the pH of the admixture making the meat non-pliable and difficult to shape.
The formed products are allowed to set in a fermenting chamber at a pre-determined temperature and for a period of time sufficient for enough acid to be produced by the bacteria or released by the acidulant to lower the pH of the admixture to a value below 5.2, typically below 5.0. The bacteria cause fermentation of carbohydrates to produce the lactic acid, which gives the sausage its characteristic flavor. The lactic acid also serves to lower the pH of the meat proteins toward their isoelectric point. This is particularly desirable because the meat proteins are less able to bind moisture as they approach their isoelectric point, thereby facilitating subsequent drying of the sausage.
The low pH level prevents further bacterial growth and otherwise makes the product biologically stable, produces an acidic flavor and sets the protein in the meat thereby giving the product a firm texture. The temperature in the fermentation chamber is typically maintained between 60° F. and 105° F. for about 7 to 14 hours.
Finally, the product is dried at a predetermined temperature and for a period of time sufficient to obtain the required finished product moisture to protein ratio (e.g., for pepperoni, 1.6:1). For dry sausage products, the drying step must be carried out under conditions which allow slow controlled uniform removal of moisture from the product yet inhibit the growth of surface mold or yeast. For example, the drying chamber is typically maintained at a temperature between 50° F. and 70° F. and kept relatively dry to inhibit the growth of mold or yeast. It generally requires several days or even weeks to reach the required finished product moisture to protein ratio depending upon the thickness of the formed product and other process conditions.
Some dry sausage is smoked prior to being dried but the primary production step is a relatively long, continuous air-drying process. Dry sausage typically requires more production time than other types of sausage. Dry sausage generally ranges from about 60% to about 80% of its original weight when sold. Semi-dry sausage is usually heated in a smokehouse to fully cook and partially dry the product.
Unfortunately, maintenance of the required conditions during the extended fermenting and drying steps can make mass production of dry and semi-dry sausage products somewhat difficult. There is a need for an economical process for making dry and semi-dry sausage products in a shorter period of time.
Surprisingly, what the inventors have found is that the invention allows one to achieve a fermentation process whereby in less than 5 hours and preferably less than 3 hours the meat admixture is at the desired pH of a fermented product without adversely affecting the textural and flavor properties even when using acidulants in the initial stages of the process.